Whether fans like it or not, Dakota Johnson and Charlie Hunnam have officially been cast to star in the big screen adaptation of Fifty Shades of Grey. Author E.L. James and producers Dana Brunetti and Michael De Luca have taken to Twitter to defend their casting decision after making the announcement on Monday, Sept. 2.

Though many fans of the erotic romance book trilogy were disappointed and even outraged over the choice, the bestselling British author, 50, tweeted her appreciation to fans on Monday. "To all the supporters, lovers and haters -- thank you so much for the passion that you have for this project," she wrote. "You all rock. All of you."

Producer Brunetti further explained the process in which they made their final casting decision. "There is a lot that goes into casting that isn't just looks. Talent, availability, their desire to do it, chemistry with other actor, etc," he tweeted Monday. "So if your favorite wasn't cast, then it is most likely due to something on that list. Keep that in mind while hating and keep perspective." He later added, "Thx to all the fans of @E_L_James FSOG for their overwhelming support of the casting choices. @MichaelDe_Luca &I can't wait to start filming."

De Luca seems confident that Johnson, 23, and Hunnam, 33, will do the books justice in bringing Christian Grey and Anastasia Steele to life on the big screen. "Auditions were stunning, incredible chemistry!" he tweeted.

Johnson, the daughter of Melanie Griffith and Don Johnson, has appeared in films like The Five-Year Engagement and The Social Network, and starred in the FOX TV series Ben and Kate. Hunnam appeared in Pacific Rim and starred as Jackson "Jax" Teller in the TV series Sons of Anarchy. The actor, however, was not James' first choice to play Grey, according to author and screenwriter Bret Easton Ellis. "Talked to E.L. James at a party over the summer: her first choice for Christian was Rob Pattinson," Ellis tweeted Monday. "E.L. James and I were at Rob Pattinson's house when she admitted that Rob was first choice for Christian."